The present application relates in general to surgical stapler instruments that are capable of applying lines of staples to tissue while cutting the tissue between those staple lines and, more particularly, to improvements relating to stapler instruments and improvements in processes for forming various components of such stapler instruments. This application also discloses devices that are related, generally and in various embodiments, to a disposable loading unit configured for connection to a reusable surgical instrument, and to surgical instruments that include a disposable loading unit.
Surgical instruments that are utilized to concurrently make longitudinal incisions in tissue and apply lines of staples on opposing sides of the incisions are known in the art. The tissue may include, for example, human tissue, animal tissue, membranes, or other organic substances. Such surgical instruments commonly include a pair of opposing jaw members that cooperate to grasp or clamp the tissue therebetween and a cutting surface that makes the incision. When employed in endoscopic or laparoscopic applications, the opposing jaw members are capable of passing through a cannula passageway. One of the jaw members typically supports a staple cartridge having at least two laterally spaced rows of staples and pushers aligned with the staples. The other jaw member is movable between an open position and a closed position, and defines an anvil having staple-forming pockets correspondingly aligned with the rows of staples in the staple cartridge. Such instruments may also include a wedge that, when driven, sequentially contacts the pushers to effect the firing of the staples toward the anvil and through the tissue.
An example of a surgical stapler suitable for endoscopic applications, described in U.S. Pat. No. 5,465,895, advantageously provides distinct closing and firing actions. Thereby, a clinician is able to close the jaw members upon tissue to position the tissue prior to firing. Once the clinician has determined that the jaw members are properly gripping tissue, the clinician can then fire the surgical stapler, thereby severing and stapling the tissue. The simultaneous severing and stapling avoids complications that may arise when performing such actions sequentially with different surgical tools that respectively only sever or staple.
However, the trauma caused to the tissue with such actions can be significant. In general, the delivery of sufficient amounts of medical agents to the site of the traumatized tissue promotes the proper sealing of the incision, reduces the possibility of infection, and/or significantly improves the healing process. The application of medical agents to the site of the traumatized tissue is often accomplished by means other than the surgical instrument that makes the incision and applies the staples. Such means generally increase the complexity and cost associated with the procedure. However, such means are often necessary because many of the surgical instruments utilized to concurrently make the incision and apply the staples are not configured to store and deliver sufficient amounts of medical agents to the site of the traumatized tissue, and the delivery of some medical agents to the site of the traumatized tissue via the surgical instrument would render the surgical instrument unsuitable for reuse.
The foregoing discussion is intended only to illustrate the present field and should not be taken as a disavowal of claim scope.